August vs. Yale Assure Lock 2: Retrofit or Replace Your Apartment Door Lock?

Retrofit or full replacement: what changes on the door

Smart locks for apartment doors come in two physical forms. A retrofit lock mounts on the inside of the door over your existing deadbolt and usually replaces only the interior thumb turn. The exterior cylinder and your current keys stay where they are. A full-replacement lock swaps the whole deadbolt, inside and out, for new hardware that typically has its own keypad and cylinder.

For renters, the main difference is what you have to put back when you leave. A retrofit lock comes off with the same screwdriver used to install it, and the original thumb turn goes back on. A full replacement means you have to store the old deadbolt and reinstall it at move-out. Until then, the key your building manager holds may not open your door. Engadget's review of the Yale Assure Lock 2 raised this point: because the lock replaces the entire deadbolt, it may not suit renters or homeowners under strict HOA rules. Whichever type you choose, check your lease first. If the lease says nothing about locks, ask your landlord in writing.

This comparison uses the August Wi-Fi Smart Lock as the retrofit example and the Yale Assure Lock 2 as the full-replacement example. Level sells both types, so it gets its own section after those two.

August Wi-Fi Smart Lock: the retrofit route

August's FAQ lists the lock at 2⅞ inches across and 1¾ inches deep. It needs at least 1⅝ inches of clearance on each side of the center of the deadbolt's mounting hole. That matters on apartment doors where a door viewer, chain or handle set sits close to the deadbolt. ButterflyMX's November 2026 review says installation takes about 10 to 15 minutes with a screwdriver. Only the interior thumb turn is replaced, so the exterior keyway and your original key stay in use.

Compatibility is the main limit. August's deadbolt compatibility list says its smart locks work only with single-cylinder deadbolts, and it names several exclusions:

Power comes from two 3V CR123 or CR123A lithium batteries. August recommends Panasonic cells and advises against rechargeables. The company quotes up to three months of battery life with Wi-Fi on and says actual life depends on how often the lock is used, deadbolt friction, Wi-Fi signal and router settings. ButterflyMX reports up to six months with Wi-Fi turned off. Wi-Fi is built in on 2.4 GHz and 5 GHz, so no bridge is needed. If Wi-Fi goes down, the lock falls back to Bluetooth.

For smart home support, August lists Alexa, Google Assistant, Samsung SmartThings and Apple HomeKit. HomeKit runs over Bluetooth, so remote control through Siri or the Home app needs a home hub such as an Apple TV or HomePod. Z-Wave is not supported. ButterflyMX describes auto-lock, location-based auto-unlock and a DoorSense magnetic sensor that reports whether the door is open. There is no keypad in the box; PIN entry needs a separately purchased Yale keypad. ButterflyMX lists the lock at $199.99, with a $229.99 MSRP, as of November 2026.

• Mortise locks

• Double-cylinder deadbolts (keyhole on both sides)

• Medeco and Mul-T-Lock deadbolts

• Single-sided deadbolts

• Low-profile Kwikset, Weiser and Baldwin models

Yale Assure Lock 2: the full-replacement route

The Assure Lock 2 replaces the whole deadbolt, including the exterior side. In exchange, the keypad is built in. Engadget's 2022 review describes several versions: a keypad with physical buttons, a touchscreen keypad, keyed or key-free models, and versions with Wi-Fi preinstalled. Yale says it fits most US and Canadian doors with boreholes up to 2¾ inches and door slabs up to 1¾ inches thick.

Engadget's reviewer installed it with a Phillips screwdriver in under 30 minutes, though that included time with customer support. The latch cavity in the reviewer's door was too shallow for calibration, and deepening it fixed the problem. The DoorSense sensor can be surface-mounted on the frame or hidden inside it. The hidden option means drilling a ⅝-inch hole in the frame, which is worth avoiding in a rental.

The lock runs on four disposable AA batteries. Engadget reports that Yale cites fire safety rules for not supporting rechargeables, and quotes Yale's estimate of about three months with Wi-Fi. If the batteries die on a key-free model, touching a 9-volt battery to contacts underneath the housing powers it long enough to get in. Bluetooth is standard on every version, and Yale sells add-on modules for Wi-Fi, Z-Wave and Matter. Engadget lists voice control through Google Assistant, Alexa and Siri, plus auto-unlock, auto-lock and multiple PIN codes with entry logs in the Yale Access app.

On price, Engadget reported launch pricing in November 2022: $160 for the button keypad, $180 for the touchscreen and from $240 for versions with Wi-Fi. At the time, Yale also offered a $4 Keyed Alike service that matched the new cylinder to your existing keys. Current prices vary by retailer and model, so compare listings before buying.

Where Level fits

Level makes locks that look like an ordinary deadbolt, with the electronics hidden inside the door, and it sells both a retrofit and full replacements. On Level's shop page in November 2026, the Level Bolt is listed at $199 and described as attaching to your existing deadbolt while keeping your current exterior hardware and keys. It works with Apple Home, Google Home, Alexa and SmartThings. The Level Lock costs $249 and the Level Lock Pro $349; both are full replacements, and the Pro lists Apple Home Key support and door-status detection. A keypad and a Wi-Fi bridge are $79 each, and Level says all its locks use CR2 batteries.

MacRumors' 2022 review of the earlier Level Lock+ adds some caveats. The CR2 battery sits in the end of the bolt, and a physical key still works if it dies. Installation took about 20 minutes, but the reviewer had to sand the deadbolt cutout and drill new strike plate holes. The reviewer's partner also picked the lock in under 30 seconds, and the review calls the price high for a lock with a standard C-cylinder. Yale also makes a retrofit option, the Yale Approach. Digital Trends described it at its April 2024 launch as Yale's first retrofit lock built for renters. It mounts only on the interior, has no built-in keypad and launched at $130, or $180 with a keypad.

The verdict: pick August if…, pick Yale if…

For most apartment renters, the retrofit approach fits the situation better. The August Wi-Fi Smart Lock keeps your building's key working, leaves the outside of the door unchanged and has Wi-Fi built in. The Yale Assure Lock 2 suits owners, or renters with written permission, who want a keypad without a separate accessory and a choice of radios.

• Pick August if you rent, your door has a standard single-cylinder deadbolt, you want management's key to keep working, and you want remote access without a separate bridge.

• Pick August if you would rather not drill anything and want an install that takes minutes to undo.

• Pick the Yale Assure Lock 2 if you own the unit or have permission to replace the deadbolt, and you want a built-in keypad or a key-free door.

• Pick the Yale Assure Lock 2 if your deadbolt is on August's incompatible list, or if you want Z-Wave or Matter modules.

• Look at the Level Bolt if you want a retrofit that is not visible from either side of the door and you use Apple Home, Google Home or Alexa.

Sources

• August Wi-Fi Smart Lock FAQ
• What Deadbolts are Compatible with August Smart Locks?
• August Wi-Fi Smart Lock Review: Features, Pricing & Alternatives (ButterflyMX)
• Yale Assure Lock 2 review: The do-everything smart lock (Engadget)
• Level Shop
• Level Lock+ Review (MacRumors)
• Yale Approach smart lock designed for renters (Digital Trends)